/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.zxing.android.view;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.text.TextPaint;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.View;

import com.google.zxing.ResultPoint;
import com.joanzapata.iconify.widget.IconTextView;
import com.zxing.android.camera.CameraManager;

import lib.grasp.R;


/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder
 * rectangle and partial transparency outside it, as well as the laser scanner
 * animation and result points.
 */
public final class ViewfinderView extends View {
    /**
     * 刷新界面的时间
     */
    private static final long ANIMATION_DELAY = 30L;
    private static final int OPAQUE = 0xFF;
    private static final int MAX_RESULT_POINTS = 5;
    /**
     * 四个绿色边角对应的长度
     */
    private int ScreenRate;

    /**
     * 四个绿色边角对应的宽度
     */
    private static final int CORNER_WIDTH = 10;
    /**
     * 扫描框中的中间线的宽度
     */
    private static final int MIDDLE_LINE_WIDTH = 6;

    /**
     * 扫描框中的中间线的与扫描框左右的间隙
     */
    private static final int MIDDLE_LINE_PADDING = 5;

    /**
     * 中间那条线每次刷新移动的距离
     */
    private static final int SPEEN_DISTANCE = 5;

    /**
     * 手机的屏幕密度
     */
    private static float density;
    /**
     * 字体大小
     */
    private static final int TEXT_SIZE = 16;
    /**
     * 字体距离扫描框下面的距离
     */
    private static final int TEXT_PADDING_TOP = 30;

    /**
     * 画笔对象的引用
     */
    private Paint paint;

    /**
     * 中间滑动线的最顶端位置
     */
    private int slideTop;

    private TextPaint textPaint = new TextPaint();

    /**
     * 中间滑动线的最底端位置
     */
    private int slideBottom;

    /**
     * 将扫描的二维码拍下来，这里没有这个功能，暂时不考虑
     */
    private Bitmap resultBitmap;
    private final int maskColor;
    private final int resultColor;

    private final int resultPointColor;
    private Collection<ResultPoint> possibleResultPoints;
    private Collection<ResultPoint> lastPossibleResultPoints;
    private CameraManager cameraManager;
    boolean isFirst;
    String mHint = "";

    public ViewfinderView(Context context) {
        this(context, null);
    }

    // This constructor is used when the class is built from an XML resource.
    public ViewfinderView(Context context, AttributeSet attrs) {
        super(context, attrs);

        // Initialize these once for performance rather than calling them every
        // time in onDraw().
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        maskColor = 0x60000000;
        resultColor = 0xb0000000;
        resultPointColor = 0xc0ffff00;
        possibleResultPoints = new ArrayList<ResultPoint>(5);
        lastPossibleResultPoints = null;

        textPaint.setColor(Color.parseColor("#66eaeaea"));
        textPaint.setTextSize(32);

        density = context.getResources().getDisplayMetrics().density;
        // 将像素转换成dp
        ScreenRate = (int) (20 * density);
    }

    public void setCameraManager(CameraManager cameraManager) {
        this.cameraManager = cameraManager;
    }

    @Override
    public void onDraw(Canvas canvas) {
        // 中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
        Rect frame = cameraManager.getFramingRect();
        if (frame == null) {
            return;
        }

        // 初始化中间线滑动的最上边和最下边
        if (!isFirst) {
            isFirst = true;
            slideTop = frame.top;
            slideBottom = frame.bottom;
        }

        // 获取屏幕的宽和高
        int width = canvas.getWidth();
        int height = canvas.getHeight();

        paint.setColor(resultBitmap != null ? resultColor : maskColor);

        // 画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
        // 扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
        canvas.drawRect(0, 0, width, frame.top, paint);        //上
        canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);    //左
        canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);//右
        canvas.drawRect(0, frame.bottom + 1, width, height, paint);//下

//		Paint mPaint = new Paint();
//		mPaint.setStrokeWidth(3);
//		mPaint.setTextSize(40);
//		mPaint.setColor(Color.WHITE);
//		paint.setAntiAlias(true);
//		mPaint.setTextAlign(Paint.Align.LEFT);
//		Rect bounds = new Rect();
//		mPaint.getTextBounds(mHint, 0, mHint.length(), bounds);
//		Paint.FontMetricsInt fontMetrics = mPaint.getFontMetricsInt();
//		int baseline = frame.bottom + fontMetrics.bottom - fontMetrics.top;
//		canvas.drawText(mHint, getMeasuredWidth() / 2 - bounds.width() / 2, baseline, mPaint);

        float textW = textPaint.measureText(mHint);
        Paint.FontMetrics fm = textPaint.getFontMetrics();
        float textH = fm.descent - fm.top;
        float textX = (width - textW) / 2;
        canvas.drawText(mHint, textX, frame.bottom + textH + 24, textPaint);


        if (resultBitmap != null) {
            // Draw the opaque result bitmap over the scanning rectangle
            paint.setAlpha(OPAQUE);
            canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
        } else {

            // Draw a two pixel solid black border inside the framing rect
            paint.setColor(0xffffffff);
            canvas.drawRect(frame.left, frame.top, frame.right + 1, frame.top + 2, paint);
            canvas.drawRect(frame.left, frame.top + 2, frame.left + 2, frame.bottom - 1, paint);
            canvas.drawRect(frame.right - 1, frame.top, frame.right + 1, frame.bottom - 1, paint);
            canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1, frame.bottom + 1, paint);

            // 这里画取景框四个角落的夹角
            paint.setColor(0xff0ec3ff);
            paint.setAntiAlias(true);
            canvas.drawRect(frame.left - CORNER_WIDTH + 2, frame.top - CORNER_WIDTH + 2, frame.left + ScreenRate
                    - CORNER_WIDTH + 2, frame.top + 2, paint);
            canvas.drawRect(frame.left - CORNER_WIDTH + 2, frame.top - CORNER_WIDTH + 2, frame.left + 2, frame.top
                    + ScreenRate - CORNER_WIDTH + 2, paint);
            canvas.drawRect(frame.right - ScreenRate + CORNER_WIDTH - 2, frame.top - CORNER_WIDTH + 2, frame.right
                    + CORNER_WIDTH - 2, frame.top + 2, paint);
            canvas.drawRect(frame.right - 2, frame.top - CORNER_WIDTH + 2, frame.right + CORNER_WIDTH - 2, frame.top
                    + ScreenRate - CORNER_WIDTH + 2, paint);

            canvas.drawRect(frame.left - CORNER_WIDTH + 2, frame.bottom - 2,
                    frame.left + ScreenRate - CORNER_WIDTH + 2, frame.bottom + CORNER_WIDTH - 2, paint);
            canvas.drawRect(frame.left - CORNER_WIDTH + 2, frame.bottom - ScreenRate + CORNER_WIDTH - 2,
                    frame.left + 2, frame.bottom + CORNER_WIDTH - 2, paint);
            canvas.drawRect(frame.right - ScreenRate + CORNER_WIDTH - 2, frame.bottom - 2, frame.right + CORNER_WIDTH
                    - 2, frame.bottom + CORNER_WIDTH - 2, paint);
            canvas.drawRect(frame.right - 2, frame.bottom - ScreenRate + CORNER_WIDTH - 2, frame.right + CORNER_WIDTH
                    - 2, frame.bottom + CORNER_WIDTH - 2, paint);

            // 绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
            slideTop += SPEEN_DISTANCE;
            if (slideTop >= frame.bottom) {
                slideTop = frame.top;
            }

            Rect lineRect = new Rect();
            lineRect.left = frame.left;
            lineRect.right = frame.right;
            lineRect.top = slideTop;
            lineRect.bottom = slideTop + 18;
            canvas.drawBitmap(((BitmapDrawable) (getResources().getDrawable(R.drawable.qr_scan_line))).getBitmap(),
                    null, lineRect, paint);

            // 不显示关键点
//			Collection<ResultPoint> currentPossible = possibleResultPoints;
//			Collection<ResultPoint> currentLast = lastPossibleResultPoints;
//			if (currentPossible.isEmpty()) {
//				lastPossibleResultPoints = null;
//			} else {
//				possibleResultPoints = new HashSet<ResultPoint>(5);
//				lastPossibleResultPoints = currentPossible;
//				paint.setAlpha(OPAQUE);
//				paint.setColor(resultPointColor);
//				for (ResultPoint point : currentPossible) {
//					canvas.drawCircle(frame.left + point.getX(), frame.top + point.getY(), 6.0f, paint);
//				}
//			}
//			if (currentLast != null) {
//				paint.setAlpha(OPAQUE / 2);
//				paint.setColor(resultPointColor);
//				for (ResultPoint point : currentLast) {
//					canvas.drawCircle(frame.left + point.getX(), frame.top + point.getY(), 3.0f, paint);
//				}
//			}

            // 只刷新扫描框的内容，其他地方不刷新
            postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top, frame.right, frame.bottom);

        }
    }

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
    }

    public void drawViewfinder() {
        Bitmap resultBitmap = this.resultBitmap;
        this.resultBitmap = null;
        if (resultBitmap != null) {
            resultBitmap.recycle();
        }
        invalidate();
    }

    /**
     * Draw a bitmap with the result points highlighted instead of the live
     * scanning display.
     *
     * @param barcode An image of the decoded barcode.
     */
    public void drawResultBitmap(Bitmap barcode) {
        resultBitmap = barcode;
        invalidate();
    }

    public void addPossibleResultPoint(ResultPoint point) {
        possibleResultPoints.add(point);
    }

    public void setHint(String mHint) {
        if (TextUtils.isEmpty(mHint)) return;
        this.mHint = mHint;
    }
}
